/*
 * Licensed to Crate.io GmbH ("Crate") under one or more contributor
 * license agreements.  See the NOTICE file distributed with this work for
 * additional information regarding copyright ownership.  Crate licenses
 * this file to you under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.  You may
 * obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 * However, if you have executed another commercial license agreement
 * with Crate these terms will supersede the license and you may use the
 * software solely pursuant to the terms of the relevant commercial agreement.
 */

package io.crate.common;


import java.util.Objects;

public final class MutableLong {

    private long value;
    private boolean hasValue = false;

    public MutableLong(long value) {
        this.value = value;
    }

    public boolean hasValue() {
        return hasValue;
    }

    public long value() {
        return value;
    }

    public void setValue(long value) {
        this.hasValue = true;
        this.value = value;
    }

    public MutableLong add(long value) {
        setValue(this.value + value);
        return this;
    }

    public MutableLong sub(long value) {
        setValue(this.value - value);
        return this;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        MutableLong that = (MutableLong) o;
        return value == that.value &&
               hasValue == that.hasValue;
    }

    @Override
    public int hashCode() {
        return Objects.hash(value, hasValue);
    }

    @Override
    public String toString() {
        return String.valueOf(value);
    }
}
